Assassin spiders

Wikipedia

Science Now, by California Academy of Sciences

Argus Courier, Petaluma, CA, October 25, 2006

Where is your God now, by unknown

Evolution

Understanding Evolution by the University of California, Berkeley Museum of Paleontology

Evolution by PBS

Tree of Life web project, offers information on the diversity and evolutionary relationships of all organisms on Earth

Arachnology
These sites are devoted to Arachnology:

International Society of Arachnology

American Arachnological Society

The World Spider Catalog by Norman Platnick

Natural History Museums in the San Francisco Bay area

California Academy of Science

Berkeley Natural History Museums:
    Essig Museum of Entomology
    Museum of Vertebrate Zoology
    Phoebe Hearst Museum of Anthropology
    UC Museum of Paleontology
    University and Jepson Herbaria
    UC Botanical Garden
    Human Evolution Research Center